The present invention generally relates to a footwear liner, and, more particularly, to a waterproof footwear liner.
It is known in the art to use a waterproof liner (or xe2x80x9cbootiexe2x80x9d) as an insert in an article of footwear to protect a wearer""s foot from water and to provide comfort and warmth to the wearer""s foot. U.S. Pat. Nos. Re. 34,890 to Sacre, 5,499,459 to Tomaro, and 5,526,584 to Bleimhofer et al. describe such waterproof booties.
The composition of such waterproof booties varies. In some booties, the waterproof material defines a continuous barrier that surrounds a user""s foot while in others the waterproof material is not continuous,, allowing water to come into contact with a user""s foot. Some booties are constructed of material that is vapor permeable/water impermeable while others are constructed of material that is both vapor and water impermeable.
The method of manufacturing such waterproof booties also varies. Some of the manufacturing processes used are labor intensive and time-consuming and some manufacturing processes do not result in a completely waterproof shoe construction. For example, in one method of making such a bootie, two fabric bootie side portions are stitched together to form a generally tubular shape. The tubular bootie is inserted within a shoe upper and the upper end of the bootie is secured to the shoe upper near the top edge of the upper, generally by stitching. A sole shaped board bottom is temporarily adhered to a shoe last by adhesive, tacks, or other suitable fasteners. The last with attached board bottom is placed within the bootie and shoemaking equipment is used to roll the lower edge of the bootie and shoe upper under the perimeter of the board bottom and secure them in position with cement. An outsole is then secured to the shoe upper and bootie using conventional methods. During this process, the waterproof lining may be damaged when rolling the lower edge of the bootie around the board bottom. If the excess material present at the lower edge of the bootie is not carefully eased into position when the bootie edge is rolled under the board bottom, folds or gaps also may result that allow faster penetration of water into the interior of the shoe.
Accordingly, there is a need in the art for a waterproof footwear liner that is easy to manufacture and that is produced using a process that has less of a potential to damage the waterproof lining of the bootie being produced.
The present invention provides a footwear liner which overcomes at least some of the above-noted problems of the related art. According to the present invention, a footwear liner is provided that comprises two sides connected at a front seam and a back seam by stitching, an inner bottom piece connected to the two sides along a bottom seam by stitching, and an outer bottom piece adhered to the inner bottom piece. Each side includes an outer layer, an inner layer, and an intermediate layer and the bottom includes an outer layer and an inner layer. The intermediate layer of each side and the inner layer of the outer bottom piece are impermeable to water and permeable to vapor. The two sides and the inner bottom piece cooperate to form a partial enclosure with a toe portion, a heel portion, and an open top portion.
In one preferred embodiment, each of the front and back seams are covered by a sealing tape such that the seams are waterproofed. In another preferred embodiment, the outer bottom piece extends outwardly beyond the seamed edge of the inner bottom piece to overlap portions of the sides adjacent the bottom seam. The overlapping portions of the outer bottom piece are adhered to the sides adjacent the bottom seam such that a waterproof seal is formed between the outer bottom piece and the sides.
The inner bottom piece is preferably formed from a flexible material, such as a oven or nonwoven fabric. The outer and inner layers of each side and the outer layer of the outer bottom piece are preferably formed from an abrasion-resistant material. Each side may further comprise a second intermediate layer formed from an insulating material and positioned between the intermediate layer and the inner layer.
According to another aspect of the present invention, a waterproof footwear liner is provided that comprises two sides connected at a front seam and a back seam and an inner bottom piece connected to the two sides along a bottom seam by stitching. Each of the front and back seams are waterproofed. An outer bottom piece is adhered to the inner bottom piece and to overlapped portions of the sides adjacent the bottom seam to form a waterproof seal between the sides and the outer bottom piece. Each side includes an outer layer, an inner layer, and an intermediate layer and the outer bottom piece includes an outer layer and an inner layer. The intermediate layer of each side and the inner layer of the outer bottom piece are impermeable to water and permeable to vapor. The two sides and the inner bottom piece cooperate to form a partial enclosure with a toe portion, a heel portion, and an open top portion.
In a preferred embodiment, the two sides are connected at the front seam and the back seam by stitching and each of the front and back seams are covered by a sealing tape.
Additional features and advantages of various preferred embodiments will be better understood in view of the detailed description provided below.